Rates of women who are opting for preventive mastectomies, such as Angeline Jolie, have increased by an estimated 50 percent in recent years, experts say. But many doctors are puzzled because the operation doesn't carry a 100 percent guarantee, it's major surgery -- and women have other options, from a once-a-day pill to careful monitoring.

Despite decades atop the dietary rogues' gallery, the flavor enhancer better known as MSG remains ubiquitous. Check the fine print on the labels of ranch dressings, instant noodle soups and chips. It's even showing up in cookbook recipes.

It's not that MSG has totally lost its stigma, but the days of its intense demonization seem to have passed. Studies have repeatedly failed to show that normal consumption causes the unpleasant reactions people complain about.

Plus, it has a flavor that's hard to beat. MSG is an easy way to create savoriness (often called umami in the food world), the rich, sometimes salty flavor you experience with Parmesan cheese or a good steak.

Maybe more to the point, Americans have moved on to fretting over other culinary villains.

"MSG has fallen to the back of the bus, basically," says Melissa Abbott, senior trend analyst with The Hartman Group, a consumer consulting and research company. "Of course, it's still an ingredient that consumers will and want to avoid, but high-fructose corn syrup and partially hydrogenated oils have just kind of jumped in front of it."

MSG is a manufactured glutamate, an amino acid found in tomatoes, walnuts, mushrooms and other foods with protein. A Japanese scientist was able to isolate the glutamate flavor in 1908, paving the way for MSG manufacturing the next year. The white crystalline additive is known for its use in Chinese foods, though it has long been a staple of packaged foods such as chips and soups. It's available commercially in seasonings like Ac'cent, Aji-no-moto and Sazon.

Cooks who swear by MSG say it intensifies the flavor of stews, meats, even vegetables.

"Used correctly, MSG can turn a really good meat into a dynamic meat," says Chris Lilly, a barbecue champion who included MSG as an optional ingredient for soy marinade in his new cookbook, "Big Bob Gibson's BBQ Book." Lilly is quick to note, though, that he always tells his customers when he uses MSG.

MSG has been produced for 100 years, often by fermenting corn, sugar beets or sugar cane. But its bad rap dates to 1968, when the New England Journal of Medicine published a letter linking Chinese food to symptoms that include numbness and weakness. MSG was fingered as a possible culprit in what was dubbed Chinese Restaurant Syndrome.

The letter struck a chord. Complaints were circulating for years when the Food and Drug Administration released an exhaustive MSG study in 1995 that concluded some people may have short-term reactions after large doses of MSG, particularly on an empty stomach. But the panel found no evidence that MSG was unsafe for most people when eaten at normal levels.

"MSG is one of those things that gets blamed for a lot of other things," says Dr. Katharine Woessner, who co-authored a study published this year that reviewed other research into possible adverse effects from normal MSG consumption.

She found little solid evidence. Woessner, an allergist and immunologist based in San Diego, says some studies have shown people who complain about MSG do not exhibit the same reaction in blind laboratory tests.

Joseph H. Hotchkiss, a professor of food science at Cornell University, says the general feeling among his peers is that MSG syndrome has been discounted. Still, the controversy is far from over. Many people still claim MSG makes them ill — just try Googling "MSG Syndrome." And at least one recent study has linked MSG to weight gain.

With MSG suspicions lingering, some food manufacturers have switched to hydrolyzed vegetable proteins, which contain glutamates at lower concentrations than MSG.

Still, supermarket shelves are sprinkled with products that contain MSG. Abbott, the food consultant, says many consumers wrongly assume MSG is gone from their cupboards. She says she'll pull cans down in consumers' kitchens and read the labels aloud.

"They're like, 'Wow! There's MSG in there?'"

MSG sales are hard to track. The Glutamate Association, a trade group, said it did not have sales figures. B&G Foods Inc. says sales for Ac'cent were up slightly in the five years through 2008, though the company reported a small sales dip for the product last year in a federal Securities and Exchange Commission filing.

Aji-no-moto and Sazon remain staple ingredients in many Asian and Latino dishes. MSG is famous for bringing out the taste in meats, but fans will use a dash in everything from soup stock to asparagus.

Robert Lu, an attorney in Phoenix, uses a touch of MSG in his beef noodle soup, stews, chili, tomato sauces and white sauce. He says it makes a noticeable difference in his pork dumplings, helping tie together the tastes of soy sauce, diced ginger, ground pepper, salt and sesame oil.

"For lack of a better word, it gives it synergy," says Lu, who grew up very familiar with MSG; his parents operated Chinese restaurants.

Anthony Michael, owner and chief cook of the Cross-Eyed Pig of Little Rock, Ark., says his customers don't care that the flavor enhancer is in some of his seasonings. He's not surprised, given that barbecue is hardly a health food.

"To be honest, I don't know if it's a Southern thing, but once people start eating barbecue, MSG is the least of the problem," he said with a laugh.

MSG's reputation has likely been buffed up a bit by the increased interest in umami (pronounced oo-MAH-mee), which is sometimes called the "fifth taste" after sweet, sour, salt and bitter.

Kara Nielsen, trend analyst with the Center for Culinary Development in San Francisco, says MSG's reputation improves as more people understand umami.

But foods watchers like Nielsen say it's doubtful MSG will ever be embraced by consumers increasingly concerned about their health and the ingredients in their food. SupermarketGuru.com editor Phil Lempert says food makers are favoring more natural ingredients to create umami flavor without MSG.

While MSG may persist, few observers expect a Renaissance.

"I think where we're headed is more natural umami — tomatoes, balsamic vinegars, Parmesan cheese," Nielsen says. "While I see MSG as doing better, the artificial world is coming under attack."

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